The invention relates to a supporting rail fitting for a drawer pull-out guide for frame furniture having a front frame with vertical and horizontal frame member, the supporting rail being secured to the frame at its front end. In furniture making, cabinets are known in which the furniture carcass is provided, at the front, with a frame which carries the fittings of the piece of furniture. To this frame are secured the hinges for a furniture door as well as the supporting rails of a pull-out guide assembly for the drawers.